Support requested in this application is for the ongoing and expanding participation of the Department of Radiation Oncology of the University of California in San Francisco in the activities of the Radiation Therapy Onncology Group. Comprised of three hospitals, Moffitt, Mt. Zion and Franklin, the Department is staffed by eleven full-time faculty members, treating 2000 new patients per year. The Department has participated in the Group since 1972, entering approximately 150 patients into the various Group protocols, pilot studies and registry protocols during the last year. The Principal Investigator is a member of the Head and Neck Committee, Combination Radiotherapy and Chemotherapy Sub-Committee and Hematopoietic Sub-Committee of the Radiation Therapy Oncology Group. The Associate Principal Investigator is Chairman or the Radiobiology Committee and a member of the Publication Committee, Experimental Design Committee, Lung Sub-Committee, Metastases Sub-Committee, Radiation Injury Sub-Committee, Hyperthermia Sub-Committee and Chairman of the Radiosensitizer/Protector Committee and all staff members serve on the working parties. The group has produced protocols for head and neck cancer, non-Hodgkin's lymphoma, brain metastasis, and hypoxic cell sensitizers, as well as providing input into other protocols. Support through this application will allow RTOG participation by the entire Department and its affiliated institution, the University of California, San Diego, Division of Radiation Oncology and increase the case accession rate to 175-200 new patients per year into the various RTOG protocols. Extensive continuing research into chemical and thermic modification of radiation effects and high LET radiotherapy is expected to lead to innovative protocols and correspondingly to increased accession of patients into studies sponsored by the RTOG.